#version 330 core
out vec4 FragColor;
in vec3 Normal;
in vec3 FragPos;
uniform vec3 objectColor;
uniform vec3 viewPos;

struct Material {
    vec3 ambient;
    vec3 diffuse;
    vec3 specular;
    float shininess;
};

uniform Material material;

struct Light {
    vec3 position;

    vec3 ambient;
    vec3 diffuse;
    vec3 specular;
};

uniform Light light;

void main()
{
    // ambient
        vec3 ambient = light.ambient * material.ambient;

        // diffuse
        vec3 norm = normalize(Normal);
        vec3 lightDir = normalize(light.position - FragPos);
        float diff = max(dot(norm, lightDir), 0.0);
        vec3 diffuse = light.diffuse * (diff * material.diffuse);

        // specular
        vec3 viewDir = normalize(viewPos - FragPos);
        vec3 reflectDir = reflect(-lightDir, norm);
        float spec = pow(max(dot(viewDir, reflectDir), 0.0), material.shininess);
        vec3 specular = light.specular * (spec * material.specular);

        vec3 result = ambient + diffuse + specular;
        FragColor = vec4(result, 1.0);

}
